The present invention relates to remotely actuated means for draining oil from a motor vehicle crankcase.
As the costs of purchasing and maintaining motor vehicles have increased considerably over the past few years, interest has risen on the part of vehicle owners in performing themselves many of the service tasks which prolong the operating life of the vehicle. Among the many tasks that the owner can do for himself is the periodic draining and changing of the motor oil. Since the drain plug is located near or on the bottom surface of the crankcase in original equipment purchased from manufacturers, the draining of a crankcase on a new motor vehicle requires two trips under the car at one of its lower points to first remove the drain plug and then to reinstall it.
Over the years, a variety of remotely actuated devices have been proposed for oil changes by the vehicle operator. Common to these devices has been the use of a flexible cable attached to a spring-loaded or otherwise normally biased-closed valve installed in the oil sump. The valve is actuated by cable tension with the cable end being available either at the vehicle instrument panel or accessible under the hood.
In practice, these devices are expensive to manufacture, normally require elaborate locking mechanisms to prevent erroneous actuation and frequently cannot be installed by the typical vehicle owner. Furthermore, the valve responsive to push-pull cable actuation has a spring-loaded arm which closes the valve upon release of the cable tension. Thus, the user does not directly effect closure through a positive application of force. This leads to uncertainty of complete closure over long periods of usage.
In addition, the character of spring-loaded valves changes over a period of time especially when the spring experiences repeated temperature cycling due to its location in proximity to the engine block. Also, the repeated actuation of the valve biasing spring may effect changes in the restoring or closure forces exerted thereby. To alert the vehicle operator of an improperly or not fully closed valve, many proposed remote drain systems have electrical warning systems including dashboard indicator lights associated therewith. The cost, complexity of installation and lack of reliability of the prior devices have limited their adoption by vehicle owners.
Accordingly, the present invention is directed to the provision of a remotely actuated oil drain device for motor vehicles in which the valve used is subjected to a positive closure force exerted by the operator. This force is intentionally made rotational to improve the reliability of the device. A further objective of this invention is to provide a simplified device that is relatively inexpensive to manufacture and to install. Thus, the ratio of benefit to cost of the present invention is such as to enable the user to realize a net saving from the use of the invention within a reasonable period of time.